Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal

[uclinux-h8/linux.git] / kernel / signal.c

diff --git a/kernel/signal.c b/kernel/signal.c
index 580a91e..7aaa51d 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -31,6 +31,7 @@
 #include <linux/nsproxy.h>
 #include <linux/user_namespace.h>
 #include <linux/uprobes.h>
+#include <linux/compat.h>
 #define CREATE_TRACE_POINTS
 #include <trace/events/signal.h>
 
@@ -3094,6 +3095,79 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s
 out:
        return error;
 }
+#ifdef CONFIG_GENERIC_SIGALTSTACK
+SYSCALL_DEFINE2(sigaltstack,const stack_t __user *,uss, stack_t __user *,uoss)
+{
+       return do_sigaltstack(uss, uoss, current_user_stack_pointer());
+}
+#endif
+
+int restore_altstack(const stack_t __user *uss)
+{
+       int err = do_sigaltstack(uss, NULL, current_user_stack_pointer());
+       /* squash all but EFAULT for now */
+       return err == -EFAULT ? err : 0;
+}
+
+int __save_altstack(stack_t __user *uss, unsigned long sp)
+{
+       struct task_struct *t = current;
+       return  __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) |
+               __put_user(sas_ss_flags(sp), &uss->ss_flags) |
+               __put_user(t->sas_ss_size, &uss->ss_size);
+}
+
+#ifdef CONFIG_COMPAT
+#ifdef CONFIG_GENERIC_SIGALTSTACK
+asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
+                                      compat_stack_t __user *uoss_ptr)
+{
+       stack_t uss, uoss;
+       int ret;
+       mm_segment_t seg;
+
+       if (uss_ptr) {
+               compat_stack_t uss32;
+
+               memset(&uss, 0, sizeof(stack_t));
+               if (copy_from_user(&uss32, uss_ptr, sizeof(compat_stack_t)))
+                       return -EFAULT;
+               uss.ss_sp = compat_ptr(uss32.ss_sp);
+               uss.ss_flags = uss32.ss_flags;
+               uss.ss_size = uss32.ss_size;
+       }
+       seg = get_fs();
+       set_fs(KERNEL_DS);
+       ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL),
+                            (stack_t __force __user *) &uoss,
+                            compat_user_stack_pointer());
+       set_fs(seg);
+       if (ret >= 0 && uoss_ptr)  {
+               if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(compat_stack_t)) ||
+                   __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) ||
+                   __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) ||
+                   __put_user(uoss.ss_size, &uoss_ptr->ss_size))
+                       ret = -EFAULT;
+       }
+       return ret;
+}
+
+int compat_restore_altstack(const compat_stack_t __user *uss)
+{
+       int err = compat_sys_sigaltstack(uss, NULL);
+       /* squash all but -EFAULT for now */
+       return err == -EFAULT ? err : 0;
+}
+
+int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp)
+{
+       struct task_struct *t = current;
+       return  __put_user(ptr_to_compat((void __user *)t->sas_ss_sp), &uss->ss_sp) |
+               __put_user(sas_ss_flags(sp), &uss->ss_flags) |
+               __put_user(t->sas_ss_size, &uss->ss_size);
+}
+#endif
+#endif
 
 #ifdef __ARCH_WANT_SYS_SIGPENDING